1. Field of the Invention
This invention relates to a computer system for converting a data stream from one protocol to another protocol. More particularly, this invention relates to a computer system for converting a data stream from the ARINC binary data bus standard 429 to the National Marine Electronics Association standard 0183.
2. Description of the Prior Art
The P-3 domed aircraft has a moving map display in the aircraft for use by the U.S. Customs agency in its surveillance programs which generally involve monitoring drug trafficking. The moving map display uses a computer installed on board the P-3 for displaying a moving map. The computer and its moving map software called xe2x80x9cfalcon viewxe2x80x9d require navigation data to be provided to the computer in the National Marine Electronics Association standard 0183 (NMEA-0183). The P-3 aircraft""s inertial navigation unit, however, provides navigation data in the ARINC-429 format.
Accordingly, there is a need to convert the navigation data provided by the P-3 aircraft""s inertial navigation unit from the ARINC-429 format to the NMEA-0183 format to allow the data to be used by the moving map display""computer. In addition, there is a need to provide a means for converting the navigation data which is small in size because of space limitations on board the P-3 aircraft.
The present invention overcomes some of the difficulties encountered in the past including those mentioned in that it comprises a highly efficient and effective computer based protocol converter for use on board aircraft with space limitations which converts navigation data from one format to another format for use by the aircraft""s moving map display computer. The navigation data is supplied by an on board aircraft inertial navigation unit to the protocol converter in the ARINC-429 protocol which converts the data to the NMEA-0183 protocol. The converted navigation data is then supplied to a moving map display on board the aircraft.
An interface board which is compatible with the ARINC-429 protocol receives ARINC navigation data from the aircraft navigational unit and stores the data prior to its transfer to a PC/AT compatible digital computer. The computer reads the data stored on the interface board including status bits which indicates the validity of the data. A computer software program within the computer converts the ARINC-429 navigational data to NMEA-0183 protocol data. The NMEA-0183 protocol data is transmitted through an RS-232 serial port to the moving map display.